System and method for balancing pressure in a container

ABSTRACT

The invention is directed to a receptacle that includes a first container configured to receive a second container and a pressure-balancing structure configured to form a pathway to balance pressure between a space exterior to the first container and an interior space, where the interior space is located between the second container and an interior surface of the first container.

BACKGROUND OF THE INVENTION

Almost everyone has used a trash or storage can that is lined with a deformable bag, such as a plastic garbage bag. This combination is illustrated, for example, in FIG. 1A, where a garbage bag 20 of a volume similar to that of a garbage can 10 may be placed within can 10 and secured at or over the top edge of can 10.

As shown in FIG. 1B, as a user fills garbage bag 20 with contents 30, the position of bag 20 may shift under the weight of contents 30 to further conform to the interior shape and volume of garbage can 10. Hence, as the bag becomes filled, the exterior surface 22 of bag 20 may be repositioned in outward direction 24 so as to become adjacent or nearly adjacent to the interior surface 12 of can 10, such that nearly the entire interior surface 12 of can 10 is in direct contact with a portion of the exterior surface 22 of bag 20.

As a user pulls the top of bag 20 upward in direction 26 so as to remove bag 20 and its contents 30 from garbage can 10 as shown in FIG. 1C, the interior space 40 between interior surface 12 of can 10 and exterior surface 22 of bag 20 may decrease in pressure and approach a vacuum. This phenomenon is explained by the universal gas law, PV=nRT. Since R is the universal gas constant 8.314472 J/(mol*K), then P₁V₁/n₁T₁=P₂V₂/n₂T₂, where P₁, V₁, n₁ and T₁ are the pressure, volume, amount of substance of gas, and temperature of interior space 40 as shown in FIG. 1D, respectively, and P₂, V₂, n₂ and T₂ are the pressure, volume, amount of substance of gas, and temperature of interior space 40 as bag 20 is pulled upward as shown in FIG. 1E, respectively. Assuming that the hypothetical of FIGS. 1D and 1E employs a constant temperature, we assume T₁=T₂. Since bag 20 seals off interior space 40 at points 42 a and 42 b, and at 43 a and 43 b as it is pulled upward, we assume a constant amount of substance of gas, so that n₁=n₂. Thus, P₁V₁=P₂V₂. Hence, as bag 20 is pulled from its position in FIG. 1D upward to its position in FIG. 1E, and interior space 40 increases in volume so that V₁<V₂, the pressure of interior space 40 necessarily decreases so that P₁>P₂, where P₁ is approximately standard atmospheric pressure, or the pressure of exterior space 30. It is this decrease in pressure that results in the approach of interior space 40 to a vacuum, thus causing a user difficulty in removing bag 20 from can 10. Sometimes, as a user is pulling bag 20 in an effort to remove it from can 10, the user may even inadvertently lift up can 10 with bag 20 and then need to pull the two apart.

The “seals” between bag 20 and can 10 at points 42 a-b and 43 a-b may not be perfect, thus allowing some leakage of air from the exterior space 30 into interior space 40. Hence, a user may ultimately be able to lift bag 20 out of can 10. This leakage, however, is often inadequate to balance the difference in pressure between exterior space 30 and interior space 40, and thus may be insufficient to allow the removal of bag 20 without significant difficulty.

Hence, it is desirable to have a solution without the above-described disadvantages, where a user may more easily remove a bag from a storage can without requiring excessive force. As will be seen, the invention provides such a solution in an elegant manner.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a diagrammatic view of a receptacle configured according to the prior art;

FIG. 1B is a diagrammatic view of a receptacle configured according to the prior art;

FIG. 1C is a diagrammatic view of a receptacle configured according to the prior art;

FIG. 1D is a diagrammatic view of a receptacle configured according to the prior art;

FIG. 1E is a diagrammatic view of a receptacle configured according to the prior art;

FIG. 2A is a diagrammatic view of a receptacle configured according to the invention;

FIG. 2B is a diagrammatic view of a receptacle configured according to the invention;

FIG. 2C is a diagrammatic view of a receptacle configured according to the invention;

FIG. 2D is a diagrammatic view of a receptacle configured according to the invention;

FIG. 3A is a diagrammatic view of a receptacle configured according to the invention;

FIG. 3B is a diagrammatic view of a receptacle configured according to the invention;

FIG. 3C is a diagrammatic view of a receptacle configured according to the invention;

FIG. 4 is a diagrammatic view of a receptacle configured according to the invention;

FIG. 5 is a diagrammatic view of a receptacle configured according to the invention;

FIG. 6A is a diagrammatic view of a receptacle configured according to the invention;

FIG. 6B is a diagrammatic view of a receptacle configured according to the invention;

FIG. 7 is a diagrammatic view of a receptacle configured according to the invention;

FIG. 8 is a diagrammatic view of a receptacle configured according to the invention;

FIG. 9 is a diagrammatic view of a receptacle configured according to the invention;

FIG. 10 is a diagrammatic view of a pressure-balancing structure configured according to the invention;

FIG. 11A is a diagrammatic view of attachment mechanisms configured according to the invention;

FIG. 11B is a diagrammatic view of an attachment mechanism and a pressure-balancing structure configured according to the invention;

FIG. 11C is a diagrammatic view of an attachment mechanism and a pressure-balancing structure configured according to the invention;

FIG. 12 is a diagrammatic view of a projection configured according to the invention;

FIG. 13A is a diagrammatic view of a projection attachment mechanism configured according to the invention;

FIG. 13B is a diagrammatic view of an attachment mechanism and a pressure-balancing structure configured according to the invention; and

FIG. 13C is a diagrammatic view of an attachment mechanism and a pressure-balancing structure configured according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention is directed to a receptacle that includes a first container configured to receive a second container and a pressure-balancing structure configured to form a pathway to balance pressure between a space exterior to the first container and an interior space, where the interior space is located between the second container and an interior surface of the first container. Thus, in one embodiment, a garbage container may be configured to receive a garbage bag that is typically made of plastic or similar material, and yet further include an air passage that allows pressure to be balanced between the volume bounded by the garbage container and the garbage bag and the exterior air pressure, allowing easier removal of the garbage bag when it is full. Of course, the invention is not limited to merely garbage containers, as it may also be utilized in different types of storage containers for wet or dry goods, pet food, industrial materials, and other applications where convenient removal of liner bags or containers is desired.

Referring to FIG. 2A, an embodiment of a receptacle 200 is illustrated. Receptacle 200 may include a first container 202 and a pressure-balancing structure 204 forming a first opening 216, a second opening 218, and a pathway 214. Pressure-balancing structure 204 may be disposed within the interior space of first container 202 as shown, with first opening 216 opening to the space 210 exterior to first container 202, and second opening 218 opening to the interior space of first container 202. In different embodiments, pressure-balancing structure 204 may be disposed in alternative positions, as long as pathway 214 formed by pressure-balancing structure 204 allows for the balancing of pressure between space 210 exterior to first container 202 and an interior space, where the interior space is located between a second container potentially received by first container 202, and interior surface 203 of first container 202.

Receptacle 200 is configured to allow for airflow between the space exterior to the receptacle and an interior space of the receptacle. Such airflow may balance differences in pressure between the two spaces. For example, a second container 206 such as the bag shown in FIG. 2B may be placed into receptacle 200 and hung over the top edge 222 of receptacle 200. A user may utilize this arrangement for purposes of placing items such as garbage into bag 206, while bag 206 is supported in an open position by receptacle 200. When bag 206 is initially placed into a container such as first container 202, an interior space 212 between the outside surface of bag 206 and the interior surface 203 may be formed. As bag 206 becomes filled with contents, interior space 212 may decrease under the weight of the contents. As bag 206 is pulled upward by a user, the pressure-balancing structure included in the receptacle prevents a vacuum from forming in volume 212 and make removing the bag 206 much more convenient. Another example is illustrated in FIG. 2C, where interior space 212 could decrease in pressure when a bag is pulled, thus nearing a vacuum. Without the pressure balancing structure, the user may then be required to use force in excess of the weight of bag 206 and its contents to remove bag 206 from first container 202.

The presence of pressure-balancing structure 204, however, may alleviate this difficulty. Assuming constant temperature, P₁V₁/n₁=P₂ V₂/n₂, where P₁, V₁, and n₁ are the pressure, volume, and amount of substance of gas of interior space 212 as shown in FIG. 2C, respectively, and P₂, V₂, and n₂ are the pressure, volume, and amount of substance of gas of interior space 212 as bag 206 is pulled upward as shown in FIG. 2D, respectively. As bag 206 is pulled upward out of first container 202, the volume of interior space 212 increases, and thus V₂>V₁. Unlike in the configuration of FIGS. 1A-E, however, pressure-balancing structure 204 may allow air to be drawn through first opening 216, pathway 214 and second opening 218, into interior space 212, thereby increasing the amount of substance of gas in interior space 212 so that n₂>n₁, and equalizing the pressure of interior space 212 with the pressure of exterior space 210 so that P₂=P₁, where P₁ is approximately standard atmospheric pressure, or the pressure of exterior space 210. This balancing of pressure between exterior space 210 and interior space 212 alleviates the problem of interior space 212 approximating a vacuum and of excess force being required to remove bag 206 and its contents from first container 202.

Referring to FIG. 3A, another embodiment of a receptacle 300 is illustrated. Receptacle 300 may include first container 302 and pressure-balancing structure 304. First container 302 may also include projection 301 at the top of first container 302. Projection 301 may be an independent structure coupled to, or alternatively, formed as an extension of, the top of first container 302. Projection 301 may be configured to allow first container 302 to support in an open position a second container such as a garbage bag by, for example, a user stretching and securing the top of the bag over the perimeter of projection 301. As shown, projection 301 may be configured such that opening 316 of pressure-balancing structure 304 remains exposed to the exterior space 310 outside first container 302. This configuration may prevent the top edge 305 of pressure-balancing structure 304 from otherwise placing pressure against a portion of the bag, possibly stretching or tearing the material as the bag is pulled downward under the weight of contents.

Another embodiment of a pressure-balancing structure 3004 is illustrated in FIG. 3B. As shown, the top edge 3005 of pressure-balancing structure 3004 may be slanted downward facing the interior of first container 3002. This configuration may alleviate the pressure that top edge 3005 may otherwise place against a portion of the bag, were it not thus structured in a slanted fashion, possibly stretching or tearing the bag. Top edge 3005 may be of a rounded or smooth design, or constructed with a soft material, so as to further alleviate the above-described pressure against the bag material.

Yet another embodiment of a pressure-balancing structure 3104 is shown in FIG. 3C. As illustrated, receptacle 3100 may include a first container 3102 and a pressure-balancing structure 3104 forming a first opening 3116, a second opening 3118, and a pathway 3114. First opening 3116 may be formed directly on the surface of first container 3102. Pressure-balancing structure 3104 may extend down to the bottom 3120 of first container 3102, so that second opening 3118 is disposed just above the bottom 3120. This configuration may also alleviate the above-described problem of potential pressure from a top edge of a pressure-balancing structure being placed against a portion of a bag, since top edge 3105 is formed as part of a wall of first container 3102, and is not exposed to the interior of first container 3102.

Referring to FIG. 4, another embodiment of a receptacle 400 may include a first container 402, within which may be disposed a plurality of pressure-balancing structures 404 a and 404 b. The use of more than one pressure-balancing structure may provide additional pressure balancing by increasing airflow into the interior space of first container 502. Although two pressure-balancing structures 404 a and 404 b are illustrated in this embodiment, an alternative number of pressure-balancing structures may be employed.

Yet another embodiment of a receptacle 500 is shown in FIG. 5. Receptacle 500 may include first container 502, within which may be disposed a U-shaped tubular pressure-balancing structure 504. Pressure-balancing structure 504 may include openings 506 at various portions of the structure, or throughout the structure. This configuration may allow for increased exposure of the vent to the potentially vacuumed area, and for substantially evenly distributed pressure balancing. Although five openings are illustrated on each segment of the U-shaped structure, an alternative number of openings may be employed.

FIG. 6A illustrates another embodiment of a receptacle 600, which may include first container 602 and pressure-balancing structure 604. As shown in FIG. 6B, pressure-balancing structure 604 may, for example, include an elongated member positioned vertically so as to support a portion of a second container 606, received by first container 602, away from the interior surface 603 of first container 602. This configuration may result in an increase of interior space 612, especially in the vicinity 612 a of pressure-balancing structure 604, thus creating a pathway 614 through which air may flow between exterior space 610 and interior space 612.

Referring to FIG. 7, another embodiment of a receptacle 700 may include a first container 702, within which may be disposed a plurality of pressure-balancing structures 704 a and 704 b. The use of more than one pressure-balancing structure may provide additional pressure balancing by increasing airflow into the interior space of first container 702. Although two pressure-balancing structures 704 a and 704 b are illustrated in this embodiment, an alternative number of pressure-balancing structures may be employed.

Yet another embodiment of a receptacle 800 is shown in FIG. 8. Receptacle 800 may include first container 802, within which may be disposed a U-shaped pressure-balancing structure 804. The use of a U-shaped structure may provide additional pressure balancing by increasing airflow into the interior space of first container 802.

FIG. 9 illustrates another embodiment of a receptacle 900, which may include first container 902 and cylindrical pressure-balancing structure 904, which may be disposed within first container 902. Pressure-balancing structure 904 may include openings 906 at various portions of the structure, or throughout the structure for substantially evenly distributed pressure balancing. The number of openings employed may be different than that shown in the figure. A user may secure a second container over the top perimeter 905 of the pressure-balancing structure 904.

Although various embodiments are disclosed, the preferred embodiment will be dependent on the manufacturability, practicality, cost, and other factors of a given application. Further, the invention is not limited to the embodiments disclosed.

A pressure-balancing structure 204, 304, 3004, 3104, 404 a-b, 506, 604, 704 a-b, 804, or 904 may be fastened to a first container using one of a variety of methods. A pressure-balancing structure may be fixedly attached, either manually or otherwise installed during manufacturing, or may be removably fastened to or simply placed in a first container. Pressure-balancing structures illustrated in FIGS. 3A-9 may also be constructed independently of a first container and configured to be attachable using one of a variety of methods. For example, pressure-balancing structure 204 may be independently constructed as pressure-balancing structure 1004 of FIG. 10.

Referring to FIG. 11A, embodiments 1106 and 1107 of attachment mechanisms are shown. Attachment mechanism 1106 may be fixedly attached or formed as an extension, either manually or otherwise installed during manufacturing, or may be removably fastened to a pressure-balancing structure 1104, as shown in FIG. 11B. This configuration may allow a user to manually attach the structure to a container such as a garbage can, as shown in FIG. 11C. In addition, one of various configurations of an attachment mechanism as known to those skilled in the art, such as but not limited to those disclosed herein may be employed. Also, one of various configurations of a pressure-balancing structure as known to those skilled in the art, such as but not limited to those disclosed in reference to FIGS. 3A-9, may be employed. The invention is not limited to any particular method of fastening between an attachment mechanism and a pressure-balancing structure, or between a pressure-balancing structure and a container.

A projection 301, 401, 501, 601, 701, or 801 may be fastened to a first container using one of a variety of methods. A projection may be fixedly attached, either manually or otherwise installed during manufacturing, or may be removably fastened to or simply placed on a first container. The projections illustrated in FIGS. 3A and 4-8 may also be constructed independently of a first container and configured to be attachable using one of a variety of methods. For example, projection 301 may be independently constructed as projection 1201 of FIG. 12.

Referring to FIG. 13A, an embodiment of a projection attachment mechanism 1303 is shown. Projection attachment mechanism 1303 may be fixedly attached or formed as an extension, either manually or otherwise installed during manufacturing, or may be removably fastened to a projection 1301, as shown in FIG. 24B. This configuration may allow a user to manually attach the projection to a container such as a garbage can, as shown in FIG. 13C. In addition, one of various configurations of a projection attachment mechanism, and one of various configurations of a projection, as known to those skilled in the art, such as but not limited to those disclosed herein, may be employed. The invention is not limited to any particular method of fastening between a projection attachment mechanism and a projection, or between a projection and a container.

Thus, the invention provides a receptacle, comprising a first container configured to receive a second container; and a pressure-balancing structure configured to form a pathway to balance pressure between a space exterior to the first container and an interior space, the interior space being located between the second container and an interior surface of the first container. The pressure-balancing structure may be attached to the first container using one of a variety of methods. This has been illustrated in several embodiments that illustrate examples of applications of the invention in practical use situations. Although some of the above embodiments are described and illustrated in the context of waste collection, the scope of the invention extends to other applications where such functions are useful. Furthermore, while the foregoing description has been put forth with reference to particular embodiments of the invention, it will be appreciated that these are only illustrative of the invention and that changes may be made to those embodiments without departing from the principles of the invention as defined by the appended claims. 

1. A receptacle, comprising: a first container configured to receive a second container; and a pressure-balancing structure configured to form a pathway to balance pressure between a space exterior to the first container and an interior space, the interior space being located between the second container and an interior surface of the first container.
 2. The receptacle of claim 1, wherein the first container is configured to hold a second container that may cause a vacuum between the second container and the first container when the second container is removed and may require force in excess of the weight of the second container and its contents to remove the second container from the first container, and wherein the pressure-balancing structure is configured to draw air into the vacuum, reducing the force required to remove the second container and its contents from the first container.
 3. The receptacle of claim 1, wherein the first container is a garbage container.
 4. The receptacle of claim 1, further comprising a projection disposed above the first container and configured to support a deformable bag in an open position.
 5. The receptacle of claim 4, wherein the projection is coupled to the first container.
 6. The receptacle of claim 4, wherein the projection is formed as an extension of the first container.
 7. The receptacle of claim 1, wherein the second container is a deformable container.
 8. The receptacle of claim 1, wherein the second container is a garbage bag.
 9. The receptacle of claim 1, wherein the pressure-balancing structure is coupled to the first container.
 10. The receptacle of claim 1, wherein the pressure-balancing structure is disposed substantially within the first container.
 11. The receptacle of claim 1, wherein the pressure-balancing structure forms a first opening at a first end of the pathway and a second opening at a second end of the pathway.
 12. The receptacle of claim 11, wherein the first opening is configured to open to the space exterior to the first container.
 13. The receptacle of claim 11, wherein the first opening is configured to open to the space exterior to the first container while the first container is holding the second container.
 14. The receptacle of claim 11, wherein the second opening is configured to open to the interior space.
 15. The receptacle of claim 1, wherein the pressure-balancing structure includes a hollow casing.
 16. The receptacle of claim 1, wherein the pressure-balancing structure is tubular.
 17. The receptacle of claim 1, wherein the pressure-balancing structure is U-shaped.
 18. The receptacle of claim 1, wherein the pressure-balancing structure contains a plurality of apertures that open to the interior space.
 19. The receptacle of claim 1, wherein the pressure-balancing structure includes an elongated member.
 20. The receptacle of claim 1, wherein the pressure-balancing structure is cylindrical.
 21. An apparatus, comprising: a pressure-balancing structure configured to form a pathway to balance pressure between a space exterior to a first container and an interior space, the interior space being located between a second container and an interior surface of the first container, wherein the first container is configured to receive a second container.
 22. The apparatus of claim 21, wherein the pressure-balancing structure includes a hollow casing.
 23. The apparatus of claim 21, wherein the pressure-balancing structure is tubular.
 24. The apparatus of claim 21, wherein the pressure-balancing structure is U-shaped.
 25. The apparatus of claim 21, wherein the pressure-balancing structure contains a plurality of apertures that open to the interior space.
 26. The apparatus of claim 21, wherein the pressure-balancing structure includes an elongated member.
 27. The apparatus of claim 21, wherein the pressure-balancing structure is cylindrical.
 28. The apparatus of claim 21, further comprising an attachment mechanism coupled to the pressure-balancing structure and configured to fasten to the first container.
 29. The apparatus of claim 28, wherein the attachment mechanism is configured to manually fasten to the first container.
 30. The apparatus of claim 28, wherein the attachment mechanism is configured to removably fasten to the first container.
 31. An apparatus, comprising: a projection structure configured to be disposed above a container and configured to support a deformable bag in an open position.
 32. The apparatus of claim 31, further comprising an attachment mechanism coupled to the projection structure and configured to fasten to the container.
 33. The apparatus of claim 32, wherein the attachment mechanism is configured to manually fasten to the container.
 34. The apparatus of claim 32, wherein the attachment mechanism is configured to removably fasten to the container.
 35. A waste container, comprising: a rigid container having an opening configured to receive a liner bag; and a vent configured to balance any air vacuum that may build up between the rigid container and the liner bag when the liner bag is removed.
 36. The waste container of claim 35, further comprising a projection disposed above the rigid container to support the liner bag in an open position.
 37. The waste container of claim 35, wherein the vent is coupled to the rigid container.
 38. The waste container of claim 35, wherein the vent is disposed substantially within the rigid container.
 39. The waste container of claim 35, wherein the vent forms an air passage between a space exterior to the rigid container and a space between the rigid container and the liner bag.
 40. The waste container of claim 39, wherein the vent forms the air passage while the rigid container is holding the liner bag.
 41. The waste container of claim 35, wherein the vent forms a plurality of openings.
 42. The waste container of claim 35, wherein the vent includes a hollow casing.
 43. The waste container of claim 35, wherein the vent is tubular.
 44. The waste container of claim 35, wherein the vent is U-shaped.
 45. The waste container of claim 35, wherein the vent is formed using an elongated member.
 46. The waste container of claim 35, wherein the vent is cylindrical. 